Device for use in sharpening domestic and other knives



A. CORNELL.-

DEVICE FOR USE H1] SJ:I ARPENING DOMESTIC AND OTHER KNIVES,

' APPuc/xmm f ED JULY 2. 1918.

1,342,275, 4 Patented une 1,1920; V

' lltorney PATENT tries.

ALFRED-CORNEIIL,.OF TONBRIDGE, ENGLAND.

DEVICE FOR USE'IN SHARPENING DOMESTIC AND OTHER KNIVES.

Specification of Letters Patent.

' Patented J mac 1, 1.920.

Applicatiomfiledluly 2,1918. Serial No. 243,082.

To all whomit-may concern:

Be itknown that I, ALrnEoGonaIn-LL, a subjectof the King. of- Great Britain,.and resident of Tonbridge, inthe county of Kent, England, have invented'new and useful Improvements Relating. to Devices for Use in Sharpening Domestic and other Knives, of which the following is a specification.

This invention relates to devices for sharpening cutting instrumentsof the type in which the reciprocation of the blade of y the instrument upon or: between the surface or surfaces of the sharpeningmeansfor the purpose of sharpening or. renewing' the cutting edge thereof causes the rotation of the cutter or sharpening means; the object of the present invention being to provide an improved device or apparatus of the kind referred to applicable for use in sharpening domestic-or table and other knives, whereby the operation of sharpening is accomplished expeditiously and efficiently and, be ing of a-simplecharaoter, is also capable of production at low cost.

According to this invention the device comprises a disk or wheel of oarborundum or other sharpening material having a V- shaped peripheral groove and arranged in such a manner that the action of drawing the'knife across the V-shape sharpening surface effects the-rotation'of the disk or-wheel and the sharpening or renewing of the cutting edge of theknife. Theaforesaid disk or wheel is mounted on a shaft or spindle the latter working-in bearings carried on a suitable base or support.

The knife to'be sharpened is inserted betweenthe faces of the V-shape groove and is guided and held against the sharpening surface by any suitable means such for eX ample as rotatable members situated at opposite sides of the axis of the diskor wheel. The said guides may be of a resilient character or be constructed of wood or other suitable or convenient material. The guides may however be constituted by a dome or cover of metal, wood or other suitable material or be in the form of a rim surrounding'the-sharpening disk or wheel, cross slots being formed in the cover or rim for the reception of the knife so as to insure the same being always presented in the required angular position in relation to the V-shape sharpening surface. The disk or wheel may be formed in one piece or be constituted by abi-part structure with a washer of leather or other suitable material arranged between the parts composing the disk or wheel. 'Ilhese-parts-may moreover. be rendered in.- terchangeable and reversible so as to lengthen the life of the disks.. In the latten case each of the faces of the disks are chamfered soas to present a more or. less sharp edge or periphery.

In order that the invention maybe readily understood.and'carried into effect I will describethe same with reference to the accompanying drawings wherein Figure 1 is an end view of the apparatus and Fig. 2 a corresponding plan.

Fig. 3 is a View showing amodified form of disk or wheel. 5

Fig. 4. is a plan view showing the apparatus provided with a modified form of guide.

A disk or wheel a of sharpening material having a V-shape groove formed in its periphery is-mounted-on a shaft or spindleb which is capable of rotation in the bearings 0 secured'to the base or support (Z. The said disk or wheel may be formed in one piece as hereinbefore described, and as shown in Figs. 1 and 2, and may be clamped between washers or collars e, e; or the construction may be that illustrated in-Fig. 3, inwhich it is constituted by a pair of disks a, a, each disk being a replica of the other and having a washer a which'may be made of leather interposed between the adjacent faces of the parts. The disk or wheel so constituted has its faces chamfered soasto present a more or less sharp edge or periphcry. The disks are-thus rendered reversible or interchangeable so that the sharpening surfaces may be changed and the life of the disks lengthened. The separate halves of the disks a a and the washer a are clamped on the spindle 6 between the washers e e. The leather washer will not be found objectionable as it will not be detrimental to the sharpening effect of the disk on the knife edge. At the open ends of the V-shape groove and at diametrically opposite points are-guides for directing the knife against the sharpening surfaces samecomprising members each of which may consist of a sleeve or cone f of rubber or other resilient material adapted to rotate by the passage of the knife blade over its surface. The sleeve 7 is placed about a pin 9 formed or provided on a plate it which is secured to the base or support (Z. The r0.- tatable sleeves or cones may be formed of wood or other suitable or convenient material. These members are so placed relatively to the V-groove in the disk or wheel a as to insure that the cutting edge of the knife shall engage the sharpening surface at the most advantageous angle, and to this end they are arranged at the entrance of the V-groove at diametrically opposite points as shown clearly in Fig. '2 there being sufficient space for the knife to pass with limited amount of play. In order further to insure that the operator shall always insert the knife in the proper position there may be substituted for the members 7 a guide (shown particularly in Fig. 4) consisting of a dome or cover 2' formed with cross slots 7s 70 therein for the reception of the knife. The dome or cover may be of metal wood or other suitable material, and instead of the dome or cover the guide may be in the form of a rim of wood or other suitable material surrounding the disk or wheel and having slots appropriately placed so as to receive the knife to be sharpened and guide and hold the same to and against the sharpening surface of the disk or Wheel. By these means the desired angularity of the V knife relatively to the sharpening disk or Wheel is assured.

In using the device the knife is inserted in the V-groove by passing the same into one of the slots 70 or between the members 7, so that the knife blade bears against opposite sides of the said members, and drawn across the surface of the disk or wheel a, the operator using a reasonable amount of pressure in so doing. Having thus drawn the knife across the wheel a, the'operation may be repeated a few times and then the knife is passed into the other slot 7". or against the other sides of the members and the operation of drawing the knife across the disk repeateda few times and so on until the desired sharpness has been obtained. By alternately subjecting the knife to the opposing sharpening faces of the disk a very even cutting edge is insured.

The device will be found eminently adapted for use in sharpening what are termed stainless steel knives as owing to the nature of the sharpening disk the latter is enabled to act only upon the cutting edge, thereby causing no damage to the surface of the blade.

When constructed of carborundum, I have observed that the disks are not detrimentally affected by grease and when dirty they can be readily removed from the shaft or spindle 'tions of said disks.

-2. A machine for sharpening knives by reciprocating the blade upon the sharpen-- ing surface so as to rotate the same, comprising a pair of oppositely beveled grinding disks, a spacing washer between said disks, a rotatable shaft whereon said disks are mounted, clamping members for securing the disks and intermediate washer in close relation upon said shaft, a support for said shaft and disks and a pair of rotatable guides disposed tangentially at diametrically opposite points of said disks and entering the V-groove constituted by the beveled portions of said disks.

3. A knife sharpening machine, comprising a shaft; grinding means fixed to said shaft and having a V-shaped peripheral groove; and means for guiding the knife blade into frictional engagement with both walls of said groove at a predetermined angle, whereby the reciprocation'of theknife will positively rotate the grinding means with relation thereto. p

4. A knife-sharpening machine, comprising a shaft; a pair of grinding disks having oppositely-beveled faces which conjointly form a V-shaped groove; a spacingwasher intermediate said disks; means for clamping said disks and Washer together in close relation on, and securing them to, said shaft; and means for guiding the knife blade into frictional engagement with both Walls of said groove, at a predetermined angle, whereby the reciprocation of the knife will-positively rotate said disks with relation thereto.

5. A knife sharpening machine, comprising a shaft; rinding means fixed to said rotate the guiding means with relation thereto.

ALFRED CORNELL. 

